Influence of alveolar echinococcosis on the experimental periodontitis

Abstract

Objective To investigate the effect of alveolar echinococcosis on the experimental periodontitis. Methods Thirty male Wistar rats were randomly divided into 3 groups: alveolar echinococcosis + periodontitis group (group A, n= 10) , periodontitis group (group B, n= 10) , control group (group C, n= 10) . Each rat of group A was received silk ligatures around their upper mandible second molars followed by an application of a periodontal pathogen, P.g, H.a, F.n and P.i, to induce periodontitis and injected by Echinococcus multilocularis at the same time. Periodontitis was induced in group B by silk ligatures as group A but without injection. The changes of body weight and periodontal index of each group were recorded dynamically. At the end of 6 months post-infection, rats were executed. Sera and gingival crevicular fluid were collected, and periodontal tissue was removed for HE staining. The IFN-γ, IL-2, IL-10 and IL-4 levels in scrum and gingival crevicular fluid were measured by ELISA. LSD-t test and variance analysis were used for statistical analysis. Results After 6 months, PPD and CAL of A group and B group were significantly heavier than the control group. PPD and CAL in A group were significantly improved than that in group B (3.53 ± 0.54 vs. 5.68 ± 0.47, 3.47 ± 0.48 vs. 5.78 ± 0.45; tPD= 9.497, PPD<0.001; tCAL= 11.102, PCAL<0.001) . Compared with group B, the pathological changes, such as gingival swelling, bleeding, periodontal pocket formation and alveolar bone resorption were significantly improved, in which the number of osteoclasts was decreased, in group A. After 6 months of experiment IL-10 and IL-4 levels in group A were significantly higher than that in group B (serum: 207 ± 35 vs. 124 ± 23, tIL-10= 6.267, PIL-10<0.001; 209 ± 71 vs. 126 ± 54, tIL-4= 2.942, PIL-4= 0.004; gingival crevicular fluid: 143 ± 56 vs. 97 ± 34, tIL-10= 2.220, PIL-10= 0.019; 178 ± 56 vs. 64 ± 35, tIL-4= 5.458, PIL-4<0.001) , and IL-10 and IL-4 levels in group C were significantly higher than that in group B (serum: 320 ± 61 vs. 124 ± 23, tIL-10= 9.507, PIL-10<0.001; 353 ± 97 vs. 126 ± 54, tIL-4= 6.465, PIL-4<0.001; gingival crevicular fluid: 293 ± 76 vs. 97 ± 34, tIL-10= 8.378, PIL-10<0.001; 310 ± 86 vs. 64 ± 35, tIL-4= 7.444, PIL-4<0.001) . IL-2 and IFN-γ levels in group A were significantly lower than that in group B (serum: 140 ± 48 vs. 184 ± 55, tIL-2= 1.906, PIL-2= 0.036; 185 ± 53 vs. 257 ± 60, tINF= 2.844, PINF= 0.005; gingival crevicular fluid: 131 ± 35 vs. 179 ± 41, tIL-2= 2.815, PIL-2= 0.005; 166 ± 45 vs. 222 ± 52, tINF= 2.575, PINF= 0.009) , and IL-2 and IFN-γ levels in group B were significantly lower than that in group C (serum: 116 ± 36 vs. 184 ± 55, tIL-2= 3.271, PIL-2= 0.002; 112 ± 24 vs. 257 ± 60, tINF= 7.095, PINF<0.001; gingival crevicular fluid: 91 ± 23 vs. 179 ± 41, tIL-2= 5.919, PIL-2<0.001; 103 ± 13 vs. 222 ± 52, tINF = 7.020, PINF<0.001) . Conclusions The protective immunity of periodontitis is a kind of Th2 immune response with IL-10 and IL-4, and the regulating of Th1/Th2 response is beneficial to improve the process of periodontitis. Echinococcus multilocularis infection had a significant influence on the Th1/Th2 balance of periodontitis in rats, with regulating the balance to Th2 predominant reaction, which had an antagonistic effect on periodontitis. Key words: Alveolar echinococcosis; Periodontitis; Th1; Th2